Ginia



H. C. COOPER.

PROOES S 0F OBTAINING GASOLENE FROM HYDROCARBON GASES.

APPLICATION FILED IMI- I8. I9".

Patented Dec. 2,1919

WITNESSES I; v I

HOWELL c. coornn, or CLARKSBUBG, WEST VIRGINIA. ASSIGNOR To Home NATURALGAS COMPANY, or PITTSBURGH, PENNSYLVANIA, A conronATIoN or WEST vin-GHVIA.

PROCESS OF OBTAINTNG GASOLENE FROM HYDROGABBON GASES.

. Specification of Letters Patent.

Patented Dec. 2,1919.

Application filed January 18, 1917. Serial No. 143,108.

To all whom it may concern:

Be it known that I, HOWELL C. Coornn residing at Clarksburg, in thecounty oi Harrison and State of West Virginia, a citizen of theUnitedStates, have invented or discovered certain new and usefulImprovements in Processes of Obtaining Gasolene from Hydrocarbon Gases,of which improvements the following is a specification.

My invention relates to the recovery from gases with which they areintermingled, of hydrocarbons whose boiling points at atmosphericpressure range from about 3& to 160 degrees (3., and which may be, andhereinafter are, designated as gasolene regardless of whether thehydrocarbons are open chain and of the parafin' or olefin series orwhether they are cyclic.

In United States Letters Patent No. 989,927, granted to G. M. Saybolt,there is disclosed a process for obtaining naphtha or gasolene fromcombustible gas of natural origin and underground sources, such method,briefly stated, in the general terms of the patent, consisting insubjecting the gas under pressure to a naphtha absorbing menstruum forthe purpose of separating from the gas such naphtha as is. liquid atatmospheric temperature and pressures, and in subsequently removing thenaphtha from the menstruum.

While my invention contemplates the use of an absorption process similarto that disclosed inthe Saybolt patent, it is, as indicated above,unlimited to the recovery of gasolene from natural gas, but extends tothe recovery from any gas or gases with which it may be intermingled. Asan example of gases, other than natural, from which gasolene may berecovered, it has been found that large quantities of gas are formed inthe practice of the various processes for cracking petroleum to producegasolene, and that such gases include gasolene hydrocarbons, that is,hydrocarbons whose boiling points lie within the above stated range.

In practising absorption processes for the recovery of gasolene fromhydrocarbon gases 7 with which it is associated, l have discovered thatsubstantially greater" quantities of gasolene maybe absorbed by a unitvolume of menstruum from a unit volume of gas treated when the gas iscaused to pass through the menstruum while the menstruum is in the formof a spray. However, when the gas is thus subjected to the menstruum,the unabsorbed gas, that is to say, the lighter combustibleconstituents, carry with it finely divided particles of the menstruum,with the resultthat there is a grad ual and continual loss of menstruum,and a corresponding ladening of the unabsorbed gas with undesirablematter. To overcome this difliculty I cause the gas, after it has passedthrough a spray of absorbing menstruum, to passthrough a liquid body ormass of absorbing menstruum, which, although not necessarily so, may bethe same menstruum as used for the spray. Such passing of the gasthrough a liquid body of menstruum not only effects the removal of thesmall particles of menstruum from the gas, but the liquid body ofmenstruum efiects a further absorption of gasolene from the gas.

The process may be best understood by explaining it with reference toapparatus whereby it may be practised. In the accon1- panying drawingforming part of my specification such an apparatus is diagrammaticallyshown.

The gas, from whatever source or sources obtained, flows to theabsorbing apparatus through the line pipe 1. The gas may be passedthrough or be otherwise subjected to a spray of absorbing menstruumeither at pressure or both. While the invention is unlimited withrespect to the pressure of the gas, it has been found that the quantityof gasolene absorbed from the gas is increased by subjectingthe gas topressure substantially in excess of atmospheric. If the gas is to besubjected to the absorbing menstruum at the line pressure, the valves 2and 3 of line 1 may be opened so that the gas flows directly to a sprayabsorber comprising a tank l and a plurality of spray nozzles 5connected to a header 6, which in turn is connected by pipe 12 to asource of menstruum supply. The gas, in flowing through the sprays ofmenstruum, becomes closely intermingled therewith with the result thatlarge proportions of gasolene-forming hydrocarbon elements are absorbedby the menstruum. I

The unabsorbed portion bf the gas, which, as already explained, carrieswith it finely ice . divided particles of the menstruum, is then passedthrough a liquid bod of menstruum tor the removal of such particles andfor the 'further absorption of asolene-forming hydro'carbons not alrea yabsorbed in the spray absorber.v The liquid body of menstruum may beheld in atank 7 provided in its bottom portion with a perforate header 8connected by a pipe 9 to the tank 4. Thus the gas may percolate throughthe menstruum within the tank and the unabsorbed lighter constituents becaught in a perforate header 10 from which they flow through a line 11to be consumed as desired.

Preferably the menstruum is used in a continuous cycle, and that used tosupply the sprays in tank 4 is, through pipe 12, and if necessary by theaid of a pump 13, taken from the liquid body of menstruum in tank 7. Toremove the absorbed hydro-carbons from the menstruum, that from tank 4is, through a pipe 14 and if necessary by the aid of a pump 15, carriedto a continuous still 16 wherein it is heated to the temperaturerequired to vaporize such hydrocarbons.

. The vapors pass off through the pipe 17 and are condensed in anywellknown or desired manner. The distilled menstruum is then, by meansof a pum 18, carried through a pipe 19 from the sti l 16 to the tank 7.To heat the menstruum as it flows to, and to cool it as it flows fromthe still, the pipes 14 and 19 lead through a heat exchanger 20, whichmay be of any desired construction. 'The menstruum flowing to the tank 7may be further cooled by a suitable cooler 21.

The apparatus thus far described may be used in the practice of myinvention when it is desired to pass the gas through the spray andliquid body absorbers at substantlally line pressure. Such procedure maybe advantageously followed when .the line pressure is substantially inexcess of atmospheric. However, thereare large quantities ofgasolene-containing gases that are obtainable only under relatively lowpressures For example, casin -head and flow-tank natural gases, both 0which are rich in gasolene, are usually obtained at or at less than,atmospheric pressure, and hence to recover large percentages of theirgasolene content it is necessary to compress them before their passagethrough the absorbers. For this purpose there 1s provided a compressor22 and cooler 23. By closing the valve 3 of line 1 and opening valves 24and 25 of branch pipes 26 and 27, respectively, the gas may becompressed and cooled before entering drawing there is shown a secondspray ab-' sorber comprising a tank 28 and nozzles 29 connected to aheader 30. Instead of formof tank 4, a special tank 31 is provided forthe menstruum, which, together with the gas is led thereto through aconduit 32 extending substantially to the bottom of the tank. Thespecific purpose of this arrange ment in this double spray absorbingapparatus is to remove from the gas the finely divided particles ofmenstruum before the gas enters the compressor 22, and to such end thelevel of the menstruum in the tank 31 is, as indicated, maintainedsubstantially above the lower end of the conduit 32 so that, the gaswill be caused to bubble through the menstruum. To cause the gas to flowthrough the low pressure spray absorber, valve 2 of line 1 is closed andvalve 33 of a by-pass 34 is opened. The further flow of the gas isthrough tank 28, conduit 32, tank 31, a pipe 35 leading from the top ofthe tank 31 (the valve 36 being open and the valve 24 closed),compressor 22, cooler 23, pipe 27, and tank '4. From tank 4 theunabsorbed gas fiows to and through the liquid body absorber in themanner already explained.

The menstruum for the low pressure spray is preferably taken from thetank 4, and for th1s purpose the header 30 is connected to the tank 4 bya pipe 37 provided with valves 38 and 39, the latter of which is placedadjacent to the header to eliminate as far as possible the foaming ofthe menstruum dueto the reduction of pressure thereon. The menstruumfrom the spra nozzles 29 is collected in the tank 31 and 1s taken fromsuch tank through a pipe 40 to the pipe 14 leading to the still 16, itbeing understood that for such operation the valve 41 will be closed.

It will be observed of the operation just described that it comprises inefiect a repetition or duplication of my improved method in its broaderaspects. In the first instance 110 the gas is passed through the sprayabsorber 28, 29, and then through the menstruum in a liquid body in thetank 31 for the purpose of removing from the gas the finely dividedparticles of menstruum carried therebyand forthe additional purpose ofeffecting further absorption of'the heavier gasolene hydrocarbons. Inthe second instance the gas is passed through the spray absorber 4, 5and then through the liquid body of menstruum in the tank 7.The-essential difference between these two pairs of absorbers is that inthe absorbers 31 and 28, 29, the gas and menstruum flow in parallelcurrents, whereas in the absorbers 7 and 4, 5 the gas and menstruum flowin counter currents.

With respect to the absorbin menstruum, various liquids having an a ityfor the gasolene-forming hydrocarbons may be used. However, thepreferred liquid is petroleum hydrocarbons having an initial specificgravity of from 28 to 55 Baum at 60 F.

It is apparent that other forms of appa- I ratus than those specificallyshown and de- 1. The process of obtammg gasolene from hydrocarbon gascontaining it, which consists in passing such gas twice through a bodyof gasolene-absorbing menstruum, the menstruum in the first passage ofgas through it being in the form of a spray and in a liquid body duringthe second passage of the gas through it, and subjecting the menstruumto a distilling operation for the removal of its absorbed gasolene.

2. The process of obtaining gasolene from hydrocarbon gas containing it,which consists in passing such gas twice through a body ofgasoleneabsorbing menstruum, the menstruum in the first passage of gasthrough it being in the form of a spray and in a liquid body during thesecond passage of'the gas through it, the menstruum for the spray eingtaken from said liquid body thereof, and finally subjecting themenstruum collected from the spray to a distilling operation for theremoval of its absorbed gasolene.

3. The process'of obtaining gasolene from hydrocarbon gas containing it,which consists in passing such gas twice through a gasolene absorbingmenstruum, the menstruum in the first passage of gas through it being inthe form of a spray and in a liquid body during the second passage ofthe gas through it, and subsequently removing absorbed gasolene fromsaid menstruum.

4. The process of obtaining gasolene from hydrocarbon gas containlng it,which consists in passing such gas twice through a,

gasolene-absorbing menstruum, the menstruum in the first passage of gasthrough it being in the form of a spray and in a liquid body during thesecond passage of the gas through it, the menstruum for the spray beingtaken from said liquid body thereof, and subsequently removing absorbedgasolene from said menstruum.

In testimony whereof I have hereunto set w my hand.

HOWELL C. COOPER. Witnesses:

THUS. MILLER, E. F. HUMEs.

